There are many emerging trends in the communications world, including the increase in mobile network technology and the rise in packet data networks. There are many types of mobile network technologies, including global systems mobile (“GSM”), code division multiple access (“CDMA”), time division multiple access (“TDMA”), and advanced mobile phone service (“AMPS”). Likewise, there are many types of packet data technologies, such as asynchronous transfer mechanism (“ATM”) and internet protocol (“IP”). Packet data technologies send packets of data, or datagrams, in which sections of a message are transmitted in scattered order and then re-ordered at a receiving node.
Mobile IP is an emerging “layer 3” type protocol that allows a mobile node to establish a wireless connection to an IP network. Mobile IP essentially has three major subsystems. A first subsystem is a discovery mechanism that provides mobile nodes with new attachment points (new IP addresses) as they move within the IP network. A second subsystem allows the mobile node to register with its “home network” when it learns its new IP address. A home network is a network, possibly virtual, that has a network prefix matching that of the mobile node's “home address.” A home address is an IP address that is assigned for an extended period of time to the mobile node. It remains unchanged regardless of where the mobile node is attached. Standard IP routing mechanisms will deliver packets destined to a mobile node's home address to the mobile node's home network.
A third subsystem allows data to be directed to the mobile node when it is away from its home network by using the registered IP address. For the sake of reference, mobile IP is discussed in greater detail in the book Charles E. Perkins, MOBILE IP: DESIGN PRINCIPLES AND PRACTICES (Computer & Engineering Publishing Group ISBN: 0-201-63469-4, 1998).
In each of these systems, packets of information are often lost when a mobile node during handoff. What is needed is a system and method to reduce the number of lost packets when a mobile node hands-off from one agent to another.